The various oxides of nitrogen, known collectively as NOx, and often present primarily in the mono-oxide form NO, form a major component of air pollution including noxious photochemical smog. NOx is typically generated when nitrogen and oxygen in the air combine at high temperatures during the burning of fuel in internal combustion engines; gas turbines; industrial, commercial and residential burners; industrial, commercial, and residential boilers; and/or other combustion applications.
Low NOx burners have been developed but may suffer from relatively high complexity and cost. Low NOx burners may further suffer from relatively poor flame stability and may be prone to flame blow-out. To overcome the tendency to undergo flame blow-out, low NOx burners may typically be operated under a relatively narrow range of turn-down ratios. Because of the effect of reduced turn-down ratio, low NOx burners may typically operate with relatively limited dynamic range with respect to power or heat output, which may be expressed as BTU/hour.
What is needed is a low NOx burner with greater simplicity and/or reduced cost compared to previous low NOx burners. What is additionally or alternatively needed is a low NOx burner that exhibits improved flame stability and/or that is amenable to operation over a relatively wide dynamic range such as to provide load matching.